Affordable Access

Publisher Website

Field adsorption of helium and neon on tungsten: An energy-resolved atom-probe study

Surface Science
Publication Date
DOI: 10.1016/0039-6028(89)90197-0


Abstract The effect of an electric field on the interaction of He and Ne with tungsten surfaces in a field ion microscope is investigated using a retarding potential analyzer combined with a magnetic sector atom probe. Appearance-energy analysis and measurements of surface-temperature dependencies, especially of electron stimulated field desorbed He n+ and Ne n+ -yields, enable the determination of binding distances, vibration frequencies and desorption energies as a function of electric field strength. The He + yield generated by field ionization above a single surface site is measured as a function of time to determine the Ne field adsorption kinetics in the presence of He. Within the accessible field strength range of 3–5 V/Å, the He-W and the Ne-W bonds are considerably strengthened, in agreement with published atom-probe FIM results. A reduction of binding distances and an increase of vibration frequencies has been measured for He ads and Ne ads, which has not been observed before. This supports the tight binding cluster model of Kreuzer and Nath that suggests formation of a weak, field-induced chemisorption bond.

There are no comments yet on this publication. Be the first to share your thoughts.